The present invention relates to a color correction head in particular, though not exclusively, for a color photographic printer and enlarger.
Due to variation in quality in color print paper and variations in overall density of color in color negatives, the color of light to be projected through color negatives during printing therefrom needs to be adjustable in a color correction head.
Color correction heads exist in which the color of the light after projection through a negative is analysed and filters are driven in and out of the path of the light, upstream of the negative, in accordance with the analysis to suit the balance of colors in the projected light to the photographic paper, whereby an accurate color print is obtained. Such conventional color correction heads have been complex and expensive, principally due to the use of stepper motors for driving the filters into position.
Many of the conventional color correction heads have employed rack and pinion drives between the stepper motor and the filter. Such drives are susceptible of backlash and stiction problems, whereby different actual color balances are in fact achieved despite identical positionings of the stepper motors on account of the direction in which the stepper motor has rotated to the desired position.
The object of the present invention is to provide an improved color correction head.